This is a complex area, where opinions, official standards, community home tests and marketing claims are constantly mixed together, and where misunderstandings spread easily. To understand it, and to understand where we stand in it, please read this page in its entirety rather than skimming it. Individual sections quoted out of context can easily be made to say something we do not say. We have been precise on purpose: about what is established fact, what is our engineering judgement, and what our tests do and do not show.
Disclaimer
This page explains product standards, published data and FamBed’s own engineering approach. It is not individual medical advice. How a family chooses to sleep with their children is always the parents’ responsibility, whatever bed they sleep in. Parents and caregivers should consider the age, health and development of their child and follow the official guidelines applicable in their country.
Family sleep is often discussed as though every child, mattress and sleeping arrangement were the same.
They are not.
A newborn in a crib is not the same situation as a mobile three-year-old sleeping beside a parent. A sofa is not a firm mattress. Two separate mattresses pushed together are not the same construction as one continuous sleeping surface. And a full-size family mattress is not a crib mattress.
This page separates three things clearly:
Established facts — regulations, standards, official health guidance and published data.
Our engineering view — the design decisions we believe make sense for a purpose-built family bed. Where something is our reasoning rather than established clinical evidence, we say so.
Our Test Library — the physical tests we perform on our products, with the method and documentation behind each result.
Our basic principle
Passing a test method from a standard is not the same thing as being certified to that standard.
Part 1
Established facts
1.0
The facts in 30 seconds
Established fact
There is currently no EN or ASTM mattress standard specifically created for a full-size family mattress shared by adults and children.
EN 16890:2017+A1:2021 covers mattresses, mattress bases and mattress toppers used in children’s cots, travel cots, cribs and suspended baby beds.[1]
ASTM F2933 / 16 CFR Part 1241 is the US crib-mattress framework covering full-size crib mattresses, non-full-size crib mattresses and certain mattresses for non-full-size cribs and play yards.[2] [3]
In US terminology, a “full-size crib mattress” is still a crib mattress, not an adult Full, Queen, King or family mattress.[2]
A full-size adult/family mattress is therefore not certifiable as an in-scope mattress under either of those crib/cot mattress standards.
Relevant physical test methods from those standards can still be useful as engineering benchmarks on a larger mattress.
We have used relevant EN-derived testing internally and are expanding the same approach into a documented Test Library.
We deliberately did not previously market our internal EN-derived test result because we did not want customers to mistake a passed test method for EN certification.
The Danish Health Authority explicitly says that, if parents choose to bed-share, the infant should have at least as much sleeping space as in its own bed. Its professional guidance also addresses bed width, firm closely fitted mattresses and the benefit of one large mattress.[5] [6]
Age matters greatly: 72% of SIDS deaths occur at 1–4 months and more than 90% occur before six months.[7]
1.1
What do EN 16890 and ASTM F2933 actually cover?
Established fact
Standard
Mattress category covered
Is a full-size adult/family mattress certifiable in this mattress standard?
EN 16890:2017+A1:2021
Mattresses, mattress bases and toppers for children's cots, travel cots, cribs and suspended baby beds
No — it is outside the standard’s product scope
ASTM F2933-25 / 16 CFR Part 1241
Full-size crib mattresses, non-full-size crib mattresses and specified mattresses for non-full-size cribs/play yards
No — it is outside the crib-mattress product scope
EN 16890’s published scope is expressly about mattresses for cots and cribs.[1]
The current US mandatory crib-mattress rule similarly applies to crib mattresses. ASTM F2933-25 became the Commission-accepted version under 16 CFR Part 1241 effective 3 May 2026, with CPSC modifications retained.[2] [3]
The US wording can be confusing because it uses the term “full-size crib mattress.” In this context, “full-size” means a standard-size crib mattress — approximately 27¼ × 51⅝ inches (about 69 × 131 cm) — not a full-size adult mattress.[2]
A 240, 300 or 400 cm family mattress is therefore not simply an oversized version of the product these mattress standards were written for.
The accredited laboratories we have contacted have told us they cannot issue ordinary, in-scope EN 16890 or ASTM F2933/16 CFR 1241 crib-mattress certification for our full-size family mattress.
That is a scope issue — not a failed-test issue.
1.2
Why use test methods from standards that do not certify our product?
Because some of the physical questions are still useful. For example:
Is the sleeping surface excessively soft?
Does a specified test body sink too deeply?
Are there unusually soft areas?
Can components separate?
Can gaps develop?
Does repeated loading materially change the surface?
Those are sensible engineering questions regardless of whether a mattress is 70 cm or 400 cm wide.
Two of them deserve a note on context. “Can components separate?” and “can gaps develop?” were written for cribs: products designed for a child sleeping alone, at times out of the caregiver’s sight and hearing, where an undetected gap can matter enormously. A shared family bed is a different situation. A caregiver is typically on the same surface, within arm’s reach, and a child in discomfort will usually make itself heard. That context changes how quickly a problem is likely to be noticed, though, as we explain in section 2.4, we still design to avoid gaps rather than rely on a sleeping adult noticing them.
Where a published test method can meaningfully be transferred to our product, we use it as a benchmark. Then we add tests for something crib-mattress standards are not designed around:
adults and children sharing one large, loaded mattress.
1.3
Why haven't we shown these tests before?
We have used relevant testing in product development, but we deliberately chose not to publish our EN-derived internal test result as a marketing claim.
There is a crucial difference between:
“Our mattress passed a firmness test based on EN 16890.”
“Our mattress is EN 16890 certified.”
The second statement would be incorrect. The same principle applies to ASTM F2933.
Because a full-size family mattress falls outside the product categories those standards certify, we did not want an EN reference, a test photo or a large PASS badge to create the impression that our product carried an official certification that cannot be issued for this type of mattress within those standards’ scope.
Passing a test method is not the same thing as being certified to the standard.
We would rather have said too little about our testing than imply a certification that does not exist for our product category.
Questions have now been raised specifically about firmness, gaps, our topper and family-bed construction. We therefore believe greater transparency is the better approach: we will show what we test, how we test it, what we measured and what the result means — without turning an internal engineering test into a certification claim.
1.4
Space is an established safety consideration — not something we invented
Official third-party guidance
One point that can disappear from discussions about bed-sharing is very simple: how much room does everyone actually have?
The Danish Health Authority explicitly addresses this. Its current public guidance states that if parents choose to sleep with an infant in their own bed, the infant should have as much sleeping space as it would have in its own bed.[5]
Its more detailed professional guidance says:
the parents' bed should be sufficiently wide;
at least 140 cm is stated, and at least 180 cm where the parents are very large/overweight;
the mattresses should be firm and closely fitted;
one large mattress is safest;
and a heavier adult can create a depression towards which an infant may roll.[6]
The Danish Health Authority’s general child-safety material repeats the same basic principle: enough room that the infant is not squeezed by the adults, firm closely fitted mattresses, and preferably one large mattress.[13]
That does not establish a clinical equation such as “a 300 cm bed reduces SIDS by X% compared with a 180 cm bed.” No such statistic has been established.
But it does establish that space, firmness, mattress joins and adult-induced deformation are relevant considerations.
1.5
Age matters — a lot
Published data
“Baby”, “child” and “bed-sharing” are frequently discussed as if the risk were constant. It is not. US NIH data show:[7]
Age
Share of SIDS deaths
1–4 months
72%
Before 6 months
More than 90%
After 6 months
Less than 10%
SIDS can still occur throughout the first year, so this should not be read as “six months = no risk.”
But neither should information about a six-week-old newborn automatically be presented as though it applies identically to a mobile ten-month-old, a two-year-old, a four-year-old or an older child.
The American five-month threshold sometimes discussed online is another thing entirely. CPSC defines an “infant sleep product” as a product marketed or intended to provide sleeping accommodation for an infant up to five months old, unless another mandatory infant-sleep rule already covers it. CPSC also states that describing sleep as “attended” or “supervised” does not by itself take an infant sleep product outside the rule.[4]
Five months is a regulatory product-category threshold — not a biological line at which sleep-related risk suddenly disappears.
1.6
Bed-sharing is not a single exposure
Published data
“Bed-sharing” can describe physically very different situations:
a firm, flat mattress — or a very soft one;
a sofa or armchair;
two mattresses with an open gap;
heavy pillows and duvets around an infant;
a parent affected by alcohol or sedating medication;
a traditional Japanese futon;
a small, crowded bed — or a large continuous family sleeping surface;
a newborn — or an independently mobile older child.
Those situations are not physically identical.
Japan is an interesting real-world example
A 2026 JAMA Network Open study notes that previous Japanese studies reported 44.9–76.2% bed-sharing across infancy. Researchers then examined 70,353 live births in Shiga Prefecture from 2018–2024 using detailed Child Death Review data; all SUID cases in the study underwent forensic autopsy.[8]
Japan — Shiga
United States
Reported Japanese bed-sharing prevalence
44.9–76.2% across infancy
—
SUID
27.0 / 100,000 live births
100.9 / 100,000 live births
SIDS
7.1 / 100,000 live births
41.7 / 100,000 live births
Data period
Shiga: 2018–2024
US comparison: 2022
Japan figures are from the 2026 Shiga Child Death Review study. The US SUID rate is from CDC, and the 2022 US SIDS rate is reported in US National Vital Statistics data. See sources [8][9][14].
What does this prove?
It does not prove that bed-sharing is risk-free. It does not prove that bed-sharing reduces SIDS. And it is not a controlled Japan-versus-US experiment. The Japanese study itself identified fatal sleep-related incidents involving mechanisms such as suffocation/strangulation in bed.[8]
But it establishes an important observation:
Very high bed-sharing prevalence can exist in a population without correspondingly high sleep-related infant mortality.
That is one reason we do not think “bed-sharing” should be treated as one single exposure with one single level of risk, independent of the surface, environment, people involved and the child’s age.
1.7
Voices in the co-sleeping community also evaluate ordinary adult mattresses
There are well-known co-sleeping educators with large audiences who focus on the practical aspects of bed-sharing.
They are not regulators, government health authorities, certification bodies or product-testing laboratories. We mention them because they are influential within the practical co-sleeping community and address subjects such as mattress firmness, flatness and recovery, bed positioning, gaps and entrapment, floor-bed setups and the selection of adult mattresses.
Many share practical checks that families can carry out at home, along with recommendations on mattress firmness, bed positioning, fall prevention and how to manage gaps. Some also provide country-specific recommendations for ordinary adult mattresses.
These recommendations include mattresses from a range of manufacturers. They are typically assessed according to characteristics such as firmness, flatness, construction and materials, not because the adult mattresses are certified to EN 16890 or ASTM F2933.
No full-size adult mattress can be certified within the crib-mattress scope of these standards. This also applies to the mattresses that co-sleeping educators recommend online.
Adult mattresses may nevertheless hold legitimate certifications relating to areas such as organic production, substances or emissions. Such certifications can be extensive and relevant, but each covers its own defined scope.
That is exactly the distinction we want to preserve:
A product can be extensively tested and certified for matters that genuinely fall within a certification’s scope without claiming to carry a crib-mattress certification that does not apply to the product.
FamBed is not affiliated with the educators or mattress manufacturers referred to. No endorsement, partnership or other association is implied.
From here: our engineering view
The sections above summarise standards, official guidance and published data. From this point we explain how we translate those facts into product-design decisions. Where a conclusion is engineering judgement rather than established clinical evidence, we say so.
Part 2
Our engineering view
Standards and epidemiological studies cannot answer every practical engineering question created by a 240–400 cm shared sleeping surface. That does not mean manufacturers should stop thinking. It means we should distinguish clearly between what is established evidence and what is engineering judgement. The following is ours — these sections should not be read as new medical claims or as statistics that have been clinically established.
2.1
If a family shares a bed, we believe more usable space makes sense
Our engineering view
The Danish Health Authority already establishes the first principle: an infant sharing the parents’ bed should have enough sleeping space.[5] [6]
Our reasoning from there is straightforward. If two adults and one or more children are going to occupy the same sleeping surface, we believe it makes more sense to give them more usable space rather than less. A 300 or 400 cm sleeping surface can physically provide:
greater separation between sleepers;
a clearly defined area for the smallest sleeper;
less need for adults and children to sleep pressed directly against each other;
more freedom for adults to change position;
and more usable space when children join the bed during the night.
We are not claiming “a 400 cm mattress reduces SIDS by X%.” There is no clinical evidence establishing such a number. Our conclusion is simpler:
Engineering judgement
If adequate sleeping space matters, designing a family bed with abundant usable space makes sense.
2.2
Purpose-built family bed versus improvised sleep solutions
Our engineering view
Many families create more sleeping space themselves. Common solutions include:
Improvised setups
pushing two independent mattresses together;
joining beds of different heights;
placing a crib beside an adult bed;
gap fillers, towels, foam or pillows between surfaces;
several separate toppers;
temporary rails / wall interfaces;
combining products never designed to function as one system.
Purpose-built family-bed system
known module geometry;
one full-width final sleeping layer;
repeatable assembly;
testable interfaces.
We understand why families do it — and we do not claim every homemade setup is unsafe. But every new connection introduces another variable:
movement · height difference · separation · compression · gap
Our approach is different:
Our approach
Design the large sleeping surface as one system from the beginning.
Our family bed is modular underneath because that makes a very large bed practical to manufacture, transport and install. But the final sleeping surface is designed so the sleeper is not lying directly on exposed mattress joins. One of the main components that makes that possible is our full-width topper.
2.3
Why we use one full-width structural topper
Our engineering view
The word “topper” sometimes creates particular concern in the United States, where separate European-style toppers are less central to normal mattress construction. Our topper is not a loose blanket, duvet, pillow or small pad underneath a child.
A loose, large duvet is not the same physical object as a tested full-width structural topper.
Our topper is a full-width structural comfort layer covering the complete family sleeping surface — above the underlying modules, spanning the complete width. It serves several practical functions.
One continuous upper surface
The supporting mattresses underneath can be modular. The sleeper lies on one topper spanning the complete width, so the normal sleeping surface does not expose the joins between the underlying mattress modules.
A component we can test
Rather than asking customers to assume that a topper behaves safely because of its name or material, we test physical questions directly. We test whether it can:
fold — and remain folded;
bunch locally;
migrate sideways;
expose an underlying join under repeated adult movement;
separate between its layers;
and how quickly it recovers after deformation.
Those are measurable questions — see the Test Library below.
Easier hygiene and maintenance
Family beds are used by children. Spills, sweat, illness and toilet accidents are normal parts of family life. A removable topper system with a removable, washable cover, used together with appropriate mattress protection, makes it substantially easier to clean and maintain the upper sleeping surface without replacing the complete structural mattress system underneath.
We do not claim that a topper makes a bed “hygienic” by itself. Our point is practical: a serviceable, removable upper layer makes cleaning, washing and replacement easier than contaminating the entire structural mattress.
In our system, the topper is therefore not an afterthought. It is one of the components that turns transportable support modules underneath into one continuous and maintainable sleeping surface above.
2.4
Gaps, entrapment, proximity and age
Our engineering view
Entrapment deserves serious attention — particularly for very young, non-mobile infants. Official safe-sleep guidance warns against an infant becoming trapped between an adult mattress and a wall, and crib/bed-rail standards devote extensive attention to openings and gaps.[15] [16]
We think it is also important to recognise that the context is different. A crib is designed to contain an infant during independent sleep while the caregiver may be asleep or elsewhere. A parent sharing the same sleeping surface is physically beside the child. That proximity can mean the caregiver may notice movement, noise or a changed position sooner than if they are in another room.
But we do not treat a sleeping parent as a safety device:
A sleeping adult cannot be assumed to detect every entrapment or airway event. Our design objective remains to avoid unnecessary trapping gaps rather than relying on a parent to wake up.
Age also changes the mechanism. A non-mobile infant who cannot reliably reposition its head or body is fundamentally different from an independently mobile toddler. CPSC’s children’s portable bed-rail framework itself defines those rails as products for children who can get in and out of an adult bed unassisted, typically around 2–5 years old. The same rules still contain entrapment requirements, showing that mobility changes the context but does not make every trapping gap irrelevant.[16]
Our engineering view is therefore:
For a non-mobile infant, wall, rail and mattress gaps deserve particular attention.
For an independently mobile toddler, the risk profile changes substantially; a gap that is critical for a non-mobile infant is not automatically the same level or type of hazard for a toddler who can reposition and get out of bed.
Any gap large enough to trap the head, neck or body is still something we believe should be avoided at any age.
2.5
Adult loading is a family-bed question crib standards do not fully answer
Our engineering view
A crib-mattress firmness test asks an important question: is the mattress surface excessively soft? We test that. But a family bed creates another obvious engineering question:
What happens to the smaller sleeper’s area when a 70, 90 or 120 kg adult lies nearby?
An adult can create:
local compression;
slope;
roll-together tendency;
tension through the topper;
and movement between underlying modules.
The Danish Health Authority specifically points out that a heavier adult can create a mattress depression towards which an infant may roll.[6]
So our test programme does not stop with an unloaded firmness test. We also measure the surface under representative adjacent adult loads. That is not an EN or ASTM certification test. It is a family-bed-specific engineering test because family beds create a loading condition that a crib-mattress test was not designed to evaluate.
Part 3
Test Library
We could create our own impressive-sounding badge and call it a “Family Bed Safety Certificate.” We deliberately do not. A self-created certificate tells a customer very little. Instead, our Test Library is built around a simple principle: show the test.
For each published test we provide:
product and revision;
test objective, equipment and load;
source test method where relevant — and where the protocol is our own, we say that too;
our procedure and predetermined acceptance criterion, where one exists;
raw measurements and result;
photos and/or unedited video where available;
and a downloadable test record when one exists.
Publishing rule
Only completed tests with a signed internal record appear as completed or PASS. Draft and planned tests are shown as scheduled — without results.
A note on the tests marked as scheduled: most of them formalise checks we have already performed in some form during product development, as part of our own practical engineering of the bed. What they have not yet been is documented under the current protocol, developed together with experienced test laboratories, and confirmed replicable by an external party. Until that standard of evidence exists, we list them as scheduled rather than passed.
Internal test · EN 16890-derived
PASS · historical
European Ball Firmness Test
Local indentation of the finished sleeping surface under the spherical-load method used by EN 16890 for cot/crib mattresses.
ID:
CS-TST-001
Product revision:
Production configuration at test time (pre-dates revision control, introduced 2026-08)
Whether the full-width structural topper can fold or stay folded by accident in a normal sleep situation, under the influence of a small child or a sleeping adult.
In our construction, topper movement cannot expose a gap between loose mattresses: the support modules sit inside one full-width cover that holds them firmly together, so the surface beneath the topper is itself continuous.
Alongside the engineering tests above, we have also performed the two at-home firmness checks widely shared in the US bedsharing community (as described in this guide) on the finished sleeping surface.
Community at-home check
Pass
At-home CD firmness check
The community CD check for surface firmness, performed on the finished sleeping surface as described in the shared guide.
ID:CS-CHK-001
Community at-home check
Pass
At-home book & ruler firmness check
The community book-and-ruler indentation check, performed on the finished sleeping surface as described in the shared guide.
ID:CS-CHK-002
3.1
How to read a test result
A PASS means: the tested product configuration met the predetermined acceptance criterion documented for that particular test. It does not mean:
EN 16890 certification;
ASTM F2933 certification;
CPSC approval;
medical certification;
or proof that every possible sleeping arrangement is risk-free.
For our own protocols, we distinguish between:
measured results, where no validated external safety threshold exists; and
internal PASS/FAIL design limits, where we have established a product specification before the test is run.
We do not create a PASS threshold after seeing the result.
3.2
What our Test Library does — and does not — mean
Our internal Test Library is intended to make our engineering work more transparent, not to create our own regulatory system. Where a test is carried out internally, we label it INTERNAL ENGINEERING TEST. Where we use a method from an existing standard, we label it METHOD DERIVED FROM EN 16890 or ASTM/CPSC-DERIVED METHOD.
We do not use:
“EN certified”;
“ASTM certified”;
“CPSC approved”;
“infant certified”;
or similar language unless an independent body with authority to issue that exact certification has actually done so.
Every test is linked to an explicit product revision (e.g. CS-MATTRESS-2026-08-A). If a safety-relevant property changes — foam specification, spring system, topper core or thickness, quilt, cover construction, attachment system or module geometry — we record whether existing results remain representative or the test must be repeated.
Part 4
Our position
4.1
Family sleep is not one uniform physical situation
We do not think the subject benefits from either extreme — “bed-sharing is always safe” or “every form of bed-sharing carries the same risk.” The physical reality is more complicated.
A newborn is not a three-year-old.
A sofa is not a firm mattress.
A crowded 140 cm bed is not physically identical to a 400 cm family bed.
A gap that is a critical hazard for a non-mobile infant is not automatically the same level or type of hazard for an independently mobile toddler.
Two loose mattresses pushed together are not the same construction as a purpose-built system with one continuous upper sleeping layer.
A loose, large duvet is not the same physical object as a tested full-width structural topper.
An unloaded mattress is not necessarily behaving the same way as a mattress carrying a 90 kg adult next to another sleeper.
The details matter.
4.2
What we commit to
Use facts where facts exist.
Say clearly when something is our engineering judgement.
Follow the product-safety law that actually applies to our products.
Use useful test methods from established standards without pretending our product carries a certification outside their scope.
Test the family-bed loading situations those crib standards do not address.
Design for space rather than crowding.
Design away unnecessary exposed gaps rather than requiring families to improvise around them.
Test the complete sleeping system — including the topper, joins and adjacent adult loading.
Publish the method and measurements behind our claims.
Never call an internal test an official certification.
That is the standard we believe a purpose-built family-bed manufacturer should be held to.
References
Sources & further reading
1
NEN — EN 16890:2017+A1:2021, scope
Children's furniture — Mattresses for cots and cribs — Safety requirements and test methods.
This page explains product standards, published data and FamBed’s own engineering approach. It is not individual medical advice. How a family chooses to sleep with their children is always the parents’ responsibility, whatever bed they sleep in. Parents and caregivers should consider the age, health and development of their child and follow the official guidelines applicable in their country.
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